586 DESCRIPTION or {Folyyastfica. 



beeu observed. The colour of these animalcules, when bearing ova, is 

 white by reflected light, and yellow by transmitted, hence the names 

 "gold and silver little fishes," so often applied to them by Joblot and 

 others ; those devoid of ova are colourless. The cilia are best seen 

 when the water is coloured ; there are from twenty-six to fifty-two 

 longitudinal rows along each side of the body ; in some rows 

 Ehreuberg counted from sixty to seventy cilia which gives 3640 

 organs of locomotion ; each cilium is placed upon a sort of little 

 knot. Fig. 329 represents an animalcule dried from clear water; 

 fig. 330 is a view of a creature feeding upon indigo, which latter 

 indicates the currents produced by its cilia; fig. 332 is an ideal 

 view, to show the structure of the nutritive organs, as stated by 

 Ehrenberg ; fig. 331 is a young specimen of the normal shape, 

 hence not produced by self-division. This species is abundant in 

 vegetable infusions, and increases so rapidly in stagnant waters, both 

 by ova and self-division, that some have thought they were produced 

 spontaneously from elementary primal matter. Size l-120th to 

 l-96th. 



Pakamecium caudatum. — Body spindle-shaped, obtuse anteriorly, 

 but attenuated posteriorly. Not found in infusions, but in ponds 

 amongst decayed sedge leaves and Conferva. Size 1-1 20th. 



P. chrysalis (M.) — Body oblong and cylindrical, equally rounded 

 at both ends ; cilia about the mouth very long. This species, like 

 P. aurelia, is often developed in such vast myriads that the water 

 Las a milky hue, the masses ascending or descending in the fluid: 

 this appearance may be produced by slightly shaking the water. 

 Found in infusions and in salt water. Size l-240th to 1-1 90th. 



P. Kolpoda (Ko/jjoda ren, M., K. cueullus, D.) — Body ovate, 

 slightly compressed ; ends obtuse, the anterior attenuated and 

 slightly bent like a hook. Found especially in infusions of Urtica 

 dioica (the stinging-nettle). Size l-240th. 



P. (?) Sinuiticum. — Body elliptical, compi'essed, the back and 

 under side carinated (keeled) ; frontal cilia indistinct. Found, 

 amongst Conferva, in a brook on Mount Sinai. Size l-288th. 



P. (?) ovutam. — Body ovate, turgid; anteriorly attenuated and 

 rounded. Found in stagnant river water. Size l-288th. 



P. comjfjressum (P. aurelia, M., Plaffiotoma co»ij)ressutn, D.) — 



